Abstract: A chair can include a base having at least one chair back attachment mechanisms that attach a back of the chair to the base of the chair. The chair back attachment mechanisms can be positioned on an upper portion of the frame of the base of the chair to support the chair back. In some embodiments, there may be a single chair back attachment mechanism or only a pair of chair back attachment mechanisms to attach the chair back to the base. The chair back can be positioned via the chair back attachment mechanisms so that there is a gap between the lower portion of the chair back and the seat. Embodiments of the chair can be armless. Other embodiments can include arms positioned above the seat on opposite sides of the seat to support arms of a user sitting on the seat of the chair.

Abstract: An adjustable back support assembly coupled to the back of a chair in which a user sits with his back spaced from the chair back. The adjustable back support assembly includes a back support that is pivotally connected to the back of the chair by a hinge. The back support is rotatable at the hinge away from the chair back and towards the back of the user to provide support thereto. The back support assembly also includes a gas cylinder having a retractable piston. The gas cylinder is connected between the back support of the adjustable back support assembly and an upstanding rigid chair backing within the back of the chair. When the retractable piston is forced outwardly from the gas cylinder, a linear pushing force is correspondingly generated by the piston to cause the back support to rotate away from the chair back and towards the back of the user.

Abstract: Seating assemblies and methods are disclosed. A seating assembly can comprise a seat, a back support, and a frame component. The frame component can extend from a bottom portion, positioned near an underside of the seat, to a top portion, configured to maintain the back support at a position above the seat. The back support can laterally extend from a left edge portion to a right edge portion and can include a spring member at or near each of the left and right edge portions. The spring member can include at least one undulation or are providing integrated compression adaptation to a user. The seating assembly can further comprise a tilt mechanism, engaged with the frame component, including one or more leaf springs and a spring contact assembly. The spring contact assembly can be positioned on a top side of the one or more leaf springs.

Abstract: According to embodiments described in the specification, a linear adjustment mechanism for a chair includes first and second structural members adapted to be connected to a chair seat and chair back respectively and coupled to one another for relative sliding movement along an axis. The mechanism further includes a rack on the first structural member extending in a direction of the axis and a pin member positioned in an opening of the second structural member for engaging with the rack. The pin member includes one or more bore openings. One or more spring members are carried by the second structural member for moving the pin member between respective limits of travel of the first and second structural members with respect to one another along the axis. The spring members are disposed through the bore opening for coupling the spring members relative to the pin member.

Abstract: Seating assemblies and methods are disclosed. A seating assembly (100) can comprise a seat, a back support (114), and a frame component (110). The frame component can extend from a bottom portion (118), positioned near an underside of the seat, to a top portion (120), configured to maintain the back support at a position above the seat. The back support can laterally extend from a left edge portion (1670) to a right edge portion (1672) and can include a spring member (122) at or near each of the left and right edge portions. The spring member can include at least one undulation or arc (1674) providing integrated rated compression adaptation to a user. The seating assembly can further comprise a tilt mechanism (408), engaged with the frame component, including one or more leaf springs (424) and a spring contact assembly. The spring contact assembly (426) can be positioned on a top side of the one or more leaf springs.

Abstract: Disclosed is a stackable chair containing a flexible back support frame mechanism that includes an improved spring system designed to allow reclining movement of a back support frame relative to a seat assembly. The back support frame and seat assembly are connected using right and left spring members disposed in a substantial surface-to-surface contact relationship with the seat assembly and back support frame members.

Abstract: A chair with a pre-pressing structure includes a chair body and a pre-pressing structure enabling the chair body to be provided with elastic restoring force. The chair is characterized in that the pre-pressing structure includes a pre-pressing member's fixed seat, a pre-pressing member, a pivoting seat, a pre-pressing positioning member and a pre-pressing angle.

Abstract: A chair with a foldable desk includes a support leg having a crossbar. A seat plate installed above said support leg includes an upper seat, a lower cover and a coupler into which the crossbar is rotatably inserted. The seat plate rotates between a vertical position and a horizontal position. A back installed above a rear side of the seat plate is capable of tilting forward and rearward with tilting means. A desk installed above a side of the support leg includes an upper plate with an attachment member on its bottom. The upper plate may swing between an upper position and a lower position within an angle range.

Abstract: The present invention relates to a vehicle seat having a seat part and having at least one backrest part which is pivotable about an axis of rotation relative to the seat part, and having a spring means which is effective between the seat part and the backrest part, wherein the backrest part comprises at least a backrest rear wall, backrest upholstery and a backrest cover. According to the invention, a spring means designed as a torsion spring is in each case arranged completely within the corresponding backrest part, is supported at the first end thereof on the backrest rear wall and acts at the second end thereof opposite the first end on an intermediate piece or on a stop of the intermediate piece, wherein the intermediate piece is arranged on the axis of rotation and is fastened to a bearing in a manner fixed relative to the frame.

Abstract: A resilient leaning position-restoring device for a height-adjustable chair back of an office chair includes a back support unit, a height-adjustable chair back disposed on the back support unit, and a resilient leaning position-restoring device disposed between the back support unit and the chair back. The resilient leaning position-restoring device essentially includes a sliding element slidable along a slot disposed on the back support unit and being pulled downward by a spring. The upper end of the sliding element extends to form a resilient member of an inverted U shape. A lower end of the resilient member is coupled to the chair back. The resilient member maintains the predetermined resilience thereof for supporting the bottom of the chair back while height adjustment of the chair back is underway. The bottom of the chair back lends proper support to the sitter's waist, regardless of an adjusted position of the chair back.

Abstract: A mounting member is adapted for joining a seat back to a frame. The mounting member includes a base and an extension projecting from the base along an axis in absence of external forces to the extension. The extension has an end distant from the base that is connectable to the seat back and that is resiliently linearly movable in directions substantially perpendicular to the axis 360° about the axis.

Abstract: A seat includes a back-up unit which includes a shaft fixed to the rear side of a backrest and the two ends of the shaft are pivotably connected to two armrests of the seat. A resilient member is mounted to the shaft and a restriction unit is connected to the shaft. The backrest tilts backward when a user sits in the seat and pivots forward to its upright position by the resilient member and the restriction unit when the user leaves from the seat.

Abstract: A resilient lower-back supporting device capable of vertical adjustment along with a backrest of a chair includes a resilient supporting unit pivotally connected between a lower end of the height-adjustable backrest and a supporting element. Configured for resilient extension and retraction, the resilient supporting unit includes an outer supporting rod and an inner supporting rod inserted therein. The two supporting rods are pulled toward each other by a spring provided therebetween. Besides, a spring is provided at an outer end of each supporting rod to bias the resilient supporting unit and the backrest toward a predetermined direction. With the backrest being vertically adjustable, and with the resilient support provided by a lower-back supporting portion at the lower end of the backrest, people of different heights are ergonomically supported especially on the lower back while sitting in the chair and are protected from back pain attributable to a prolonged sitting posture.

Abstract: A chair has a seat 1 and a backrest 2 and the backrest 2 is allowed to be tilted backward by elastic deformation of right and left back frame devices 4. The right and left back frame devices 4 each are composed of two unit frames 43 and 44. The back frame device 4 has a main portion 4a which are disposed outside the right and left sides of the seat 1, upper inward portions 43a and 44a which are connected to an upper rear end of the main portion 4a, lower inward portions 43b and 44b which go under the seat 1 from a lower end portion of the main portion 4a, and forward end portions 43c and 44c which are integrally connected to the lower inward portions 43b and 44b. The forward end portions 43c and 44c are fixed to the base 7.

Abstract: A buffering device for chair is disposed between a first part of a chair and a second part which is capable of pivoting with respect to the first part and between a first position and a second position. The buffering device is capable of keeping driving the second part to swivel back to the first position, and when the second part is located at the second position, the amount of deformation of an elastic member of the elastic member increases.

Abstract: A backrest device comprises at least one backrest and at least one connecting unit having two springs, two jointing members and a connecting member. Each spring comprises a first end and a second end. Each jointing member is provided with at least one first engaging block for engaging with the first end of the spring. The connecting member is provided with at least one second engaging block for engaging with the second end of the spring and is fixed to a chair stably. When the user sits in the chair with his back leaning against the backrest, since the springs are flexible, which can enable the backrest to be freely adjusted and moved in response to the movement of the back of the user, producing a buffering effect and providing a comfortable support to the back of the user, so the user will feel comfortable.

Abstract: A back rest for a chair with a back support and a back surface secured to the back support and able to swivel about a two-axis joint. The joint has a joint plate connected to the back surface, an element made of an elastic material that supports the joint in a ground position, and a chamber to accommodate the elastic element, connected to the back support. The joint plate is arranged in the receiving chamber between two elements made from an elastic material, holding the joint in a ground position and each being supported against the receiving chamber, and it can swivel about the two swivel axes. When the joint is placed under load, the two elastic elements are only subjected to compression. There are no tension-loaded connections which break under loading and can result in the joint falling apart.

Abstract: A movable backrest for a chair comprises a frame that is fixed to the chair, at least a flexible connecting element connected to the frame, and at least a backrest connected to the connecting element. Since the connecting element is flexible, the backrest and the back of the user can be moved simultaneously along with the movement of the back of the user, providing a comfortable support to the back of the user.

Abstract: A back includes an integrated articulating back frame and a back support. The back frame has a lower segment pivoted to a chair control, an upper segment for thoracic support, and links forming a four-bar linkage with the upper and lower segments, with a joint being formed at the lumbar region. The back support is stretchable in limited directions to accommodate shape change in the articulating back frame but to provide adequate support to a seated user. Upon receiving a rearward pressure on the lumbar joint, the back frame itself changes shape. The pivot locations in the four bar linkage create a mechanism that simultaneously controls rotational and translational movement of the upper segment during flexure of the lumbar. The back frame is close to the back support to provide significant design flexibility, but permit substantial lumbar flexure. Various back supports are contemplated that accommodate articulation of the back frame.

Abstract: A backpost for use in wooden dining chair. The backpost unit provides reclining movements for a wooden chair of the type having a stationary frame section within which the backpost unit is secured. The backpost unit consists of an interlocking mechanism with minimum components and requires minimum maintenance and provides a solid and reliable reclining mechanism. The chair enables the user to secure an accurate posture of sitting during eating and also enables the user to enjoy a relaxing posture while sitting on the same dining chair.

Abstract: Cushioning device to cushion a backrest with respect to the seat of a chair or suchlike. The device comprises a first supporting element connected to the backrest, a second supporting element connected to the seat and pinned to the first supporting element, and a spring connected both to the first supporting element and to the second supporting element, to allow a reciprocal elastic oscillation, of a determined amplitude, between the backrest, which can oscillate, and the seat, which remain still. In a wall of the first supporting element a lodging seat is provided to lodge, at least partially, the spring in such a manner that the longitudinal axis of the spring is substantially aligned with respect to the first supporting element.

Abstract: A “task” chair intended primarily for a person working at a computer terminal has a back provided with a pair of upright struts that incorporate respective parallelogram linkages operative to increase the curvature of the lumbar region of the seat back while at least substantially maintaining the contour of the upper region of the backrest when a person leans back in the chair.

Abstract: A chair comprising a support structure bearing a seat and a backrest, in which the backrest comprises a bearing portion and a connecting portion for connection to the support structure, in which the backrest is tiltable rearwards relative to a resting position under a rearwards thrust applied by the user and elastically returns to the resting position when the rearwards thrust ceases. The rearwards tilting of the backrest is formed in part by an elastic detonation of the bearing portion and in part by a displacement of at least a part of the connecting portion relative to the support structure.

Abstract: A flexible chair back provides a preferred elastic effect than conventional plastic chair backs, which comprises a back supporting board having a flexible member integrally extended from the back supporting board, a rear board and a spring sandwiched by the back supporting board and the rear board. The spring enhances the elasticity of the flexible member, so that the flexible member pushes a seated person's back quite adaptively, and therefore a person can sit against the chair back with comfort for a long period of time.

Abstract: A vehicle seat has a back mounted to pivot on a seat proper by a locking mechanism, and urged forwards by a torsion bar formed by a metal wire which has two ends fixed respectively to the back and to the seat proper. The metal wire constituting the torsion bar forms at least one spiral comprising a plurality of adjacent turns.

Abstract: A chair having a seat and a back rest. The back rest is attached to the seat via a back rest support element. The flat spring can be made from a non-metallic material, such as from fiberglass. The back rest support element comprises a flat spring disposed under pretension. In one embodiment, the seat is disposed upon a seat support structure having four legs. Preferably, the legs are splayed outside the perimeter of the seat, so that the chair is stackable with chairs of like design. The seat and the back rest can be made from a lightweight plastic material, and that the support structure can be made from tubular steel.

Abstract: A chair of the type having a seat and a separate seat back including a chair frame with a rear segment. The seat back is movably secured to the frame by a mounting mechanism whereby the seat back is capable of pivoting about at least two axes of rotation. The seat may also be connected to a fixed seat support by at least one mounting mechanism, allowing the seat to be pivoted about at least one axis of rotation.

Abstract: A chair has a pair of spaced-apart back support mounting members, a lower back support adapted to support the lower portion of the back of a person seated on the chair and mounted on the back support mounting members for pivotal movement about a pivot axis located at substantially the vertical centerline of the lower back support, and an upper back support adapted to support the upper portion of the back of a person seated on the chair and mounted on the back support mounting members for pivotal movement about a pivot axis located at substantially the vertical centerline of the upper back support.

Abstract: A back mounting arrangement for a chair in which a back member is pivotable relative to a seat member. The back mounting arrangement includes a flexible bar-type pivot member interposed between the seat member and the back member. The pivot member includes an upper section received within a passage associated with the back member, and a lower section received within a passage associated with the seat member. The pivot member is formed of a resilient material and is flexible so as to enable the back member to be pivoted rearwardly relative to the seat member, and to provide a forward bias to the back member for resisting rearward pressure applied to the back member. A limit member, in the form of a limit strap, is engaged with the pivot member for limiting rearward pivoting movement of the back member relative to the seat member. The limit strap includes an opening which receives a protrusion associated with the pivot member.

Abstract: A seat part (20) of a functional chair is connected to a head part (16) of the pedestal (10) via a joint (18) comprising elastomeric material (38) such that it can be tilted relative to the head part (16) against spring force. A backrest part (28) is similarly connected via a joint (26) to a backrest support (24) which allows the backrest part (28) to tilt relative to the backrest support (24) about a horizontal axis and about an axis which is parallel to the longitudinal direction of the backrest.

Abstract: A seating unit having two adjacent and mutually pivotal support elements 3, 4) pivotal between an initial position and a maximum flexed position. A spring element (12) is secured between the support elements (3, 4) and biases the support elements (3, 4) into the initial position. The spring element (12) comprises a base member (13) arranged in an area between the support elements (3, 4). At least one engagement element extends from the base member (13) into cavity (14, 15) in one of the support elements (3, 4) such that the support elements (3, 4) may pivot relative to each other. The engagement element is provided with a rigid stop (17, 17') projecting from the base member (13) to define the maximum flexed position of the support elements. The engagement element is further provided with a leaf spring (18, 18'; 68) to restore the support elements (3, 4) to their initial position.

Abstract: In a chair having a backrest which can be reclined backwardly against the action of spring means, the latter comprises a leaf spring having its central portion operatively connected to the base structure of the chair and its ends connected to two side arms which support the backrest.

Abstract: An infant-restraining protective seat (1) includes a seat back (3) tiltably attached to the body (7) of a seat portion via a turning shaft (20), with the seat portion (2) and seat back (3) being foldable. A torsion spring (54) is interposed between the body (7) of he seat portion and the seat back (3). The torsion spring (54) is adapted to assume a free state when an upper hook pin (52) is at an .alpha. position. Under these conditions, the seat back (3) is capable of tilting forward to .beta. under its own weight. When the seat back 3 is tilted in the direction of .beta., shock is mitigated by the torsion spring (54). When the seat back (3) is tilted toward .gamma. and .delta., half-latching and play in the back-and-forth direction are prevented. When the infant-restraining protective seat (1) is not in use, the protective seat is folded up to reduce its size and can then be stored. The seat (1) can be carried about and set up on a vehicle seat much more easily.

Abstract: A backrest recliner mechanism for a vehicle seat or the like includes a connector and a locking mechanism which both pivot about the same line. The backrest recliner mechanism also utilizes the energy of the backrest biasing spring to aid in the return of the locking mechanism from a disengaged to engaged position. The mechanism is actuated by a handle which minimizes the forces required to unlatch the locking mechanism. The backrest recliner mechanism is designed so as to incorporate a minimum number of parts and also to be easily and quickly assembled with minimal modification of the seat shell.

Abstract: A seating furniture includes a frame having a backrest mounting portion; a seat disposed on the frame; and a backrest disposed adjacent the backrest mounting portion. The backrest includes upper and lower backrest parts extending respectively above and below the backrest mounting portion. The furniture further has a connecting member which attaches the backrest to the backrest mounting portion and which includes a leaf spring secured to the backrest mounting portion and the backrest. The leaf spring positions the backrest in a predetermined angular orientation and resiliently resists an angular displacement of the backrest from the predetermined angular orientation.

Abstract: Seating apparatus comprising a seat support carrying a seat, a back element pivoted to said seat support which can articulate between forward and rearward positions in relation thereto, and torsion bar means extending between the back element and the seat support which resiliently bias said back element towards the forward position.

Abstract: An apparatus for the attachment of a lower back support upholstery by means of a spring to a back rest support, which is a four-sided tube. Preferably there are three springs formed from rubber and metal and which are arranged in an isosceles triangle. Access holes in the four sided tube facilitate the attachment of the springs.

Abstract: A chair support structure including a pair of transversely spaced struts maintained in substantially fixed relationship to each other, the axes of the struts being inclined with respect to the horizontal and defining an imaginary surface therebetween, an integral rigid member having two upper end portions spaced from each other and two lower end portions spaced from each other and being inclined oppositely to said struts with respect to the horizontal and positioned intermediate the struts to intersect the surface defined thereby, a first tension member connecting the integral rigid member at its upper end portions with the struts at a position above said intersection, a second tension member connecting the integral rigid member at its lower end portions to the struts near their bottoms, and a third tension member connecting the integral rigid member to the struts above said intersection in a position different from said first tension member to gradually inhibit forward pivoting.

Abstract: A chair for business or home use comprises a rotatable seat supported on a single leg at the bottom of which is a ball bearing caster. The leg is connected by a telescopically extensible arm to a pivot post which projects upwardly from the center of a circular base plate on which the ball bearing caster is adapted to roll as the chair swings around the pivot post. The chair may also have a back rest which is mounted for universal movement on a back support which extends rearwardly from an upper portion of the chair leg and then upwardly. The ball bearing caster comprises a larger ball retained in a socket and resting on a circle of smaller bearing balls so that the larger ball can rotate freely in all directions. Alternatively the ball bearing caster comprises a plurality of balls in a retainer.

Abstract: In order to achieve the necessary flexible curve according to the natural curve of the human spine in the field of back supports, the back support, attached relatively rigidly in its lower section to the seat, is constructed increasingly more flexibly towards the top. So that the desired course of the spine-like curve can also be achieved at the upper end of the shoulder pad connected to the back rest when the chair is "loaded", a spring member which becomes progressively "harder" is mounted in the connecting element between the end of the back rest and the shoulder pad.

Abstract: A chair back mounted on a chair back support plate is pivotally connected by a resilient arrangement to a housing slideably mounted on a vertical post. The resilient arrangement includes a member of a resilient material with ends, each end having enlarged heads with an opening extending through the heads and a pivot groove positioned between the enlarged heads. Upon application of an external force, the chair back pivots about the groove and compresses the enlarged heads thereby closing the opening through the enlarged heads.

Abstract: An adjustable seat back mechanism for a chair of the type such as a secretarial posture chair which includes a vertical support to which a seat back is slidably mounted. The seat back mechanism includes a channel shaped support plate secured to the seat back of the chair, a housing and a latching arrangement carried by the housing for permitting stepwise vertical adjustment of the housing and support plate relative to the vertical support post of the chair. A pivotal connection between a housing and the support plate is accomplished by a resilient arrangement. In one embodiment, the resilient arrangement takes the form of a pair of rubber-like blocks. In an alternative embodiment, the resilient arrangement takes the form of a leaf spring and plate disposed between the housing and support plate. The spring plate, support plate and housing are interconnected by a pin.

Abstract: A back support for a chair having a seat and a back pad. The support includes an elongated support member attached at one end to the chair seat and at its other end to the back pad. The back pad attachment includes a flexible block attached to the back pad with a clip disposed in part between the block and the pad. The clip includes top and bottom portions disposed on either side of the block with one of the portions including a lip along one edge thereof. The block and the clip are forced into a pocket on the support member. The pocket includes a slot to receive the lip thereby securing the back pad to the support member. The flexing of the block permits the back pad to pivot thereby adjusting the back pad position to the contour of the back of a person seated on the chair.